Loops of generally strip material are attached to the surface of many different types of articles. Belt loops on pants are one example for which the present invention has particular utility, but loops on other articles such as handbags could also be formed in the way described herein.
Different types of belt loops are typically used on different types of pants. One type of loop which is often used on casual pants such as blue jeans has both ends of the loop material folded over and attached to the pants in suitably spaced relation through the folded ends. Apparatus for forming this type of loop is disclosed in U.S. Pat. No. 3,699,907 which is assigned to the Duplan Corporation of which the instant assignee, The Rochester Button Co., is a division. The apparatus described in this patent folds over both ends of the loop and then transfers the folded loop to sewing apparatus such as a bar tacker which sews through each folded end of the loop and the garment to attach the loop to the garment with both ends of the loop folded under. One end of the loop can also be left unfolded and sewn to the garment without being turned under the loop. Inasmuch as each folded-under end is covered by the loop itself, however, the patented apparatus cannot sew only the flat under-part of one end of the loop to the garment.
The type of loop having one end folded over and sewn to a garment through the fold but the other end turned under the loop and sewn to the garment only through the flat end under the loop is sometimes referred to in the trade and is described herein as a style loop. The style-type loop is preferred for less casual pants such as slacks. There has thus long been a demand for apparatus which can form the distinct type of style loop and attach it to a surface.
One device which can form style loops and attach them to pants is identified by the manufacturer, AMF Incorporated, as a Semi-Automatic Belt Loop Machine (SABL). This machine requires short strips of loop material which are pre-cut to the length for the loops to be attached to the pants. Each individual loop-strip is placed upside down in a feed channel which is parallel to and (inconveniently) underneath the arm of a sewing machine. One end of the loop-strip is fed from the channel to the needle for sewing to the pants. The pants are then shifted to the position for sewing the other end of the loop, and at the same time a plate under the feed channel engages the loop to turn it over the already sewn end until the free end of the loop flips from its rearward, upside down position in the channel to a forward, rightside up position with an end portion of the loop overhanging the end of the plate. A wiper then extends downwardly across the end of the plate and inwardly thereof to fold the free end of the loop about the plate for sewing to the pants through the folded end.
The machine just described is only semi-automatic in that it requires each individual pre-cut loop-strip to be fed into the machine by hand. These strips must be placed under the sewing arm so that an unskilled operator would have to peer around the sewing head and arm in order to find the place for inserting the individual loop-strips. The operation of the device, moreover, folds the folded-over end of the loop only after the flat end of the loop has been attached to the pants so that the maximum speed with which it can complete a loop includes the time for both sewing the loop to the pants and folding over the one end. Finally, it does not appear that the machine positively engages the loop at all times in folding over the one end of the loop, but rather requires some resiliency in the loop material during the folding operation so that the one end will flip over for wiping about the plate to form the fold.